Thanks for posting. This study had also gotten our attention. However, it poses a problem in the very attempt to establish a baseline to compare against. We had never heard of the California flood of 1961-62. This flood certainly occurred before the bulk of greenhouse gases were released by the industrial revolution. The researchers seek to use this event as a baseline, but exactly how often would such floods occur without greenhouse gases?

Humans have been in the North and South America for much longer than Western technology. Even the Spanish records would provide some data for another century or so. It seems like a reasonable guess drought played a role in the downfall of the Anasazi and other civilizations of North and South America. The case for human induced climate change would be much stronger if baseline climate could be accurately determined in a such a way to explain the role of climate in the known downfall of ancient civilizations in the Americas and elsewhere.